In a large majority of equipment cooling or heating of the equipment is performed by closed circuit systems. Closed circuit systems support conditioning of a cooling or heating fluid that in a large majority of cases would be water. Undetected or late detected fluid leakage could cause damage to the equipment where the fluid system resides. In order to detect a leakage, in such systems fluid inflow and outflow are monitored. Typical examples of such closed fluid systems are cooling systems of electronic equipment, high power lasers, ultraviolet lamps, electric generators, motors of power stations and others, where even a small fluid leakage can cause significant damage.
Monitoring of fluid inflow or supply and outflow or return in a closed circuit or even in an open circuit system allows to calculate the difference between the fluid inflow and the fluid outflow. If a difference between the fluid inflow and fluid outflow exists, there is a fluid leak in the system. The monitored values of the fluid inflow and outflow could be quite large, hundreds and thousands of liters per minute, although a leakage of a fraction of liter could sometimes cause significant damage to the cooled or heated equipment. Especially dangerous are internal fluid leakages that do not appear immediately on the surface and it takes time to discover them.
U.S. Pat. Nos. 3,484,085, 4,133,373, 4,705,060, 4,944,253, 5,188,143, 5,357,241, 6,481,265 and patent applications publications 2003/0110834 and 2013/0333447 disclose different leakage measurement and detection systems.